The field of the disclosure relates generally to circuit breaker devices, and, more specifically, to self-resetting biasing devices for current limiting circuit breaker trip systems.
Known current-limiting circuit breakers interrupt circuit faults and limit the short-circuit current by utilizing a variety of electromechanical mechanisms to open the problematic circuit in a sufficiently short enough time to prevent damage to electrical components other than the circuit breaker. At least some known current-limiting circuit breakers impose an upper limit on the current that may be delivered to a load through the circuit breaker with the purpose of protecting the circuit generating or transmitting the current harmful effects due to a short-circuit or a similar problem in the load. Also, at least some known current-limiting circuit breakers utilize more than one method for sensing and reacting to increasing current (I) above a rated current and tripping the affected circuit. Further, at least some known current-limiting circuit breakers are designed to meet various requirements set forth by standards-making bodies.
In at least some known trip systems for current limiting circuit breakers, a biasing force on the trip lever increases linearly as the trip lever rotates. This results in a low biasing force for lower level current, and a large biasing force at high level fault current. In at least some known trip systems, the large biasing force at high current levels may make it difficult to trip the circuit breaker in 4-5 milliseconds (ms) in order to clear a fault in a half cycle of a fault current. As a result of the large biasing force at high current levels in at least some known trip systems, it is challenging to provide a current limiting circuit breaker device that satisfies both Underwriters Laboratories (UL) and International Electrotechnical Commission (IEC) requirements.